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Columbia, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
443-542 5 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2004-06-25   
443-542 6 CLMAMDSRRS0  9212 VERIZON MARYLAND, INC. 238   2004-12-20   
443-542 7 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-02-02   
443-542 8 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2007-09-01   
443-542 9 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2007-01-19   
443-545 A BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 0 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-09-25   
443-545 1 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 2 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 3 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238      
443-545 4 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-04-04   
443-545 5 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-06-03   
443-545 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-08-01   
443-545 7 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-03   
443-545 8 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2016-09-19   
443-545 9 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2008-10-03   
443-546 A CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-546 0 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2011-02-03   
443-546 1 CLMAMDCBRP0  9212 VERIZON MARYLAND, INC. 238      
443-546 2 BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2007-08-24   
443-546 3 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-09-15   
443-546 4 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2006-09-15   
443-546 5 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2010-07-11   
443-546 6 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-06-22   
443-546 7 BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2010-08-01   
443-546 8 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-10-10   
443-546 9 BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-04-24   
443-583 A PIVLMDPKXFX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-583 0 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2016-03-03   
443-583 1 PIVLMDPKXFX  829J PAETEC ITEL, LLC 238      
443-583 2 BLTMMD91DS2  2596 QUANTUM TELECOMMUNICATIONS, INC. - MD 238   2016-01-31   
443-583 3 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-03-31   
443-583 4 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2014-03-31   
443-583 5 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2014-09-01   
443-583 6 BLTMMDCH40Z  5562 METROPCS, INC. 238   2015-05-29   
443-583 7 BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238   2014-09-16   
443-583 8 BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2015-05-14   
443-583 9 BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2014-11-08   
443-656 A PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-656 0 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 1 BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-22   
443-656 2 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-656 3 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 4 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 5 CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-656 6 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 7 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 8 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 9 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-11   
443-718 A PIVLMDPKXEX  829J PAETEC ITEL, LLC 238   2025-04-01   

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Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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